1. Field of the Invention
The present invention relates generally to fluid containers and more particularly to an electroplating tank or the like for containing caustic and acid solutions, such tank including a novel hood arrangement for aiding ventilation and for reducing acid splash.
2. Description of the Prior Art
In the electroplating industry, tanks containing hundreds of gallons of fluids such as sulfuric acid, hydrogen fluoride and other caustic chemicals are in common use. Hazards associated with the use of such devices are that the fluids often corrode tank materials causing leaks in the tank or failure of the weakened tank due to its inability to withstand the pressures of the heavy fluids.
Another danger is that fumes from a tank may injure the lungs or eyes, or otherwise harm the health of persons using the tank. Fumes and vapor from the tank may also cause corrosion of nearby equipment.
The possibility of fire is another hazard that must be dealt with in electroplating operations. The source of most fires is the electric heater typically used to heat fluids in the tanks. These heaters typically consist of an electric heating element encased in a cylinder which extends down into the fluid. If the fluid level in a tank should drop below the hot part of the heater cylinder, or if the cylinder should be damaged by corrosion, the resulting heat developed can ignite the acid gas mixed with air and cause a fire.
Due to the nature of the operation, common practice today is to operate open top electroplating tanks. In some electroplating processes fluid in the tank is agitated by gas bubbles forced out of holes in pipes resting on the floor of the tank. This bubbling action plus splash caused when articles are loaded or unloaded to/from the tank can result in acid getting on the clothes and exposed parts of the body of persons using the tank. The bubbling action also increases the fumes and vapor coming off the acid.
Typically, ventilation outlets are located in a wall on the side opposite that in which the tank is loaded/unloaded in order to draw the fumes away from persons operating the tank. However, because the fumes and vapors are heavy, this arrangement usually fails to provide adequate removal and a dangerous amount of gas fumes escapes the ventilator, particularly on the side of the tank opposite the ventilator inlet where the draw is weakest.